FIG. 1 is a perspective view of a known mower, typically referred to as a mid-mount Z type mower. The mid-mount Z mower of FIG. 1 includes a pair of rear drive wheels 43 each of which is driven by a hydro (hydrostatic or hydraulic) pump so that two pumps are provided, steering levers 15, 16, frame 17, cutter or mower deck assembly 12 below which the blades cut grass, operator seat 18 for a seated operator, gas tank 19, combustion engine 20 located behind the seat, and front caster wheels 37. The mower is a zero radius turning self-propelled power lawn mower, and includes first and second hydro pumps (not shown) for controlling first and second corresponding wheel motors (not shown), so that the first and second independently driven rear drive wheels 43 may be driven independently in order to conduct zero radius turns.
The cutter deck assembly is typically adjustable upwardly/downwardly in order to (a) adjust the cutting height of the mower, and/or (b) allow an operator to move the cutter deck assembly upwardly to a heightened position for storage and/or transport and then back to a lower position following the storage and/or transport for cutting grass. Unfortunately, many deck lift systems are unduly complicated and require too many parts to be commercially and/or practically advantageous.
U.S. Pat. No. 6,868,658, commonly owned and hereby incorporated herein by reference, discloses a deck lift system including an automatic resetting latch. The latch system of an embodiment of the '658 patent includes a deck lift lever for selectively raising and lowering a cutter deck assembly, a pivoting latch for selectively engaging a projection in order to maintain the cutter deck assembly at a given height, and a spring coupled to the pivoting latch in a manner such that the spring biases the pivoting latch in a first rotational direction toward the projection when a longitudinal axis of the spring is on a first side of a pivot axis of the latch. Moreover, the spring biases the pivoting latch in a second opposite rotational direction away from the projection when the axis of the spring is on a second side of the pivot axis of the latch. The longitudinal axis of the spring is switched from the first side of the latch pivot axis to the second side thereof during raising of the cutter deck assembly and is thus first biased by the spring in the first rotational direction toward the projection, and is thereafter biased by the spring in the second opposite rotational direction when the longitudinal axis of the spring is switched to the second side of the pivot axis.
While the deck lift system, including the latch arrangement, of the '658 patent are excellent for their intended purposes, the system is complicated and not always desirable from a commercial perspective in certain applications; there remains room for improvement to simplify the deck lift system.